Driven largely by smart phones, tablets, and video streaming, the amount of wireless data handled by wireless networks has risen markedly and is expected to continue to rise by orders of magnitude over the next ten years. In addition to the sheer volume of data, the number of devices is expected to continue to grow exponentially, possibly reaching into the billions of devices, along with radically higher data rates. Different applications will place different requirements on the performance of future wireless networks. Future wireless networks are expected to be highly flexible, highly efficient, open, and customizable for customers and consumers.
In a Long Term Evolution (LTE) wireless network, the eNodeB (eNB) is responsible for running the radio resource control (RRC) protocol and is in charge of many decisions such as commanding the user equipment (UE) to measure neighboring cells in a particular priority order and initiating handover to neighbors based on a policy. In today's products, this policy is often hard-coded with limited means of configuration, and is difficult to change.
3GPP LTE and Wi-Fi use centralized architectures where user sessions are managed in highly centralized data centers or central offices. Due to the proliferation of highly functional user equipment (UE) that allow users to multi-task, for example, surf the internet, instant message and stream videos at the same time, the handling of user sessions in the data centers or central office can approach the performance limits of the data centers or central office.
In addition, with the increased deployment of small cells, het-net, machine to machine (M2M), and networks of devices, where thousands or millions of devices are attached, there are a large number of user sessions, some of which are more local (i.e., originate and terminate in nearby locations), while others are more distant. Each of these devices may be mobile. A core network anchors the Internet protocol (IP) sessions centrally and thus is able to maintain an IP session while a device transitions between layer 2 anchor points. Furthermore, the core network architecture, which is based on tunnels to a fixed anchor point, is cumbersome and inefficient. The packet data network (PDN) gateway (PGW) becomes a bottleneck in terms of the number of sessions that can be managed, and it becomes a central point of failure because it maintains so much state about the mobile nodes (MNs).